Updated last day versus updated last seven days versus updated last thirty days.
Are those counted by the day they are posted within the system, or the date that appears as the entry?
For example; lj_user_a posts 7 entries on one day, dated July 1 through July 7. Is that counted as activity on the day they post it, or on all seven days?
lj_user_b posts one entry a day, July 1 through July 7. That should be counted as active for all 7 days?
Therefore, a the usual stats query that is run on July 9 would show lj_user_a as having updated more than seven days but less than thirty days ago, but lj_user_b as having updated less than seven days ago, and less than thirty days ago, yes?